Commands using perl (369)

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a short counter
Maybe you know shorter ?

count the number of specific characters in a file or text stream
In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex). It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes. The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count. I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check. The approach can be made in to a function and then included in .bashrc or similar. e.g. $ count_chars() { tr -d -c "$1" | wc -c; } In this form it provides a versatile character counter of text streams :)

Copy uncommitted changes from remote git repository
Copy changed files from remote git repository, _including binary ones_, staged and unstaged alike. Note that this command doesn't handle deleted files properly.

convert a line to a space

See system users

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Email yourself after a job is done
This is a two part command that comes in really handy if you're running commands that take longer than you're willing to wait. The commands are separated by the semicolon(;) The first command is whatever you're attempting to do. The second commands emails you after the job completes.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Gets the english pronunciation of a phrase
Usage: say hello world how are you today

Watch a dig in progress
Watch a dig in progress


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